The RF Rain Sensor operates on radio frequency. Suspends watering in case of rainfall. For use with DUAL and TEMPO water timers, by means of a dedicated interface ( product code (8480). The RF Rain Sensor is designed for open air installation, exposed to rainfall, using a special stainless steel bracket supplied with the product. No electrical connections are required: RF coverage up to 30 m. Powered by 2 x 1.5 V AA alkaline batteries.